``Thin Flap'' LASIK is Safe and Effective for Patients Previously Ill-Suited for LASIK Surgery, Study Finds.

Business Editors/Health & Medical Writers

ASCRS Annual Meeting

PHILADELPHIA--(BW HealthWire)--June 3, 2002

Technique Can Benefit an Estimated 10-12 Million Americans With

High Degrees of Nearsightedness and/or Thin Corneas

A study presented yesterday at the Annual Meeting of the American Society of Cataract and Refractive Surgery (ASCRS) reported that LASIK performed with a "thin flap" 130-micron microkeratome head is safe and effective for patients with high degrees of nearsightedness (myopia) and/or thin corneas.

Previously considered poor candidates for LASIK surgery, an estimated 10 to 12 million Americans suffer from high degrees of nearsightedness (typically more than -6 diopters) and/or thin corneas (typically less than 550 microns).

"The results of this study demonstrate that surgeons can consistently perform safe and effective LASIK on patients who until now have been forced to pursue other vision correction options," said study author Paul Dougherty, M.D., medical director of Dougherty Laser Vision Institute (Camarillo, Calif.) and a clinical instructor at UCLA's Jules Stein Eye Institute. "'Thin flap' LASIK using a 130 micron head can treat a broad range of patients with high degrees of nearsightedness and/or thin corneas."

The study, entitled "Thin Flap LASIK: Comparison of Visual Outcomes and Safety Using a 130 Micron Microkeratome Head Versus a 160 Head" (ASCRS Session 2-p), compared results from 135 eyes in the 130-micron group to 237 eyes in the 160-micron group. The results for both groups were found to be similar in terms of vision improvement and flap complications. No flap complications were noted in the "thin flap" group. Results were achieved using the BD K-3000 Microkeratome manufactured by BD Ophthalmic Systems (Franklin Lakes, New Jersey).

During LASIK surgery, a thin flap of corneal tissue is cut and peeled back to allow a laser to reshape the cornea underneath. The cutting is performed using a device called a microkeratome that creates a flap typically 160 to 180-microns thick -- a measure equal to the thickness of one or two human hairs. While this approach works well for the majority of patients, it is often ill suited for those with high degrees of nearsightedness and/or thin corneas, because their correction requires more tissue to be removed with the laser and/or they have less initial cornea tissue available. With "thin flap" LASIK, surgeons peel back a thinner 130-micron flap, thus retaining more of the patient's corneal tissue with which to work.

Despite the very encouraging study results, Dr. Dougherty warns that the "thin flap" technique has its limits. "Even with the success of the 130-micron microkeratome head, I strongly advise against performing LASIK on any patient whose cornea is thinner than 500-microns," he said.

About Paul Dougherty, M.D.

Dr. Dougherty is medical director and chief refractive surgeon at Dougherty Laser Vision in Camarillo, Calif. He also serves as a clinical instructor at UCLA's Jules Stein Eye Institute. Performing laser vision correction since 1993, he has authored numerous studies that have been published in leading peer-reviewed journals. He also lectures internationally on a wide range of refractive and corneal surgery issues. Dougherty Laser Vision: 1821 Daily Drive, Camarillo, CA 93010; 805/987-5300; www.doughertylaservision.com